1. Field of the Invention
The present invention relates to an elevator group management system and an elevator assignment method for assigning a most suitable elevator from a plurality of elevators which respond to an elevator call which takes place on a particular floor (hereinafter named a "hall call").
2. Description of the Related Art
Recently, a most suitable elevator is rationally and quickly assigned from a plurality of elevators which respond to a hall call which takes place on a particular floor by means of a small computer such as a microcomputer or the like.
In addition, recently, the assignments of such elevators are controlled by using a plurality of group management control devices. An advantage of this method is that a task group for calculating a time for which each elevator responds to a hall call is distributed to a plurality of group management control devices and thereby a large number of processes can be shared by them. The task group is activated with a control command by a main task with which one of the group management control devices is provided. The main task is a task for controlling the overall assignments of the elevator group. The main task executes a process for determining an elevator which should respond to the hall call in accordance with information collected from the task group.
Nevertheless, in such an elevator group management system, as the scale of the elevator system becomes large, that is, the number of hall calls due to an increase of floors and elevators becomes large, the group management control device having main task is concentratedly loaded. Thus, when a plurality of hall calls take place nearly at the same time, the later hall calls are processed with a long time delay.